^start of line
\d+a digit, repeated at least once
\.the literal . (4610 / 568 / 2E16)
\Kresets the starting point of the reported match. Any previously consumed characters are no longer included in the final match
\d+a digit, repeated at least once
Non-Capturing Group(?:,\d+)+ +repeats the group contents below at least once:
,the literal , (4410 / 548 / 2C16)
\d+a digit, repeated at least once
g modifier: global. Finds all matches instead of stopping after the first
m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string